273 adjustable rockers on 360, very little oil to springs

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SBM4theW!n

SBM4theW!n

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Finished putting 273 rockers on my LA 360 this spring and pulled off the oil cap a few days ago and while running there was very little oil coming out of the top hole of the rocker. Even when I revved it up I could see it pulsing but just a very slight trickle at best. I shut it off and looked at the springs and they looked almost dry. Everything seems fine, but I remember the old stamped rockers throwing oil everywhere.

Is this normal or a problem? I've heard the springs need oil to stay cool and don't want to hurt my new pushrods or valves.

Running 5-30 synthetic oil (hot), good oil pressure
Previous stamped rockers threw tons of oil
273 rockers with stock banana shafts, cleaned up with new adjusters
Shafts oriented correctly
At most 2 thin shims per rocker used to center rocker on valve
Car gets a lot of spirited driving through mountain roads hitting 6k often
Comp's Magnum 280H cam with matching Comp springs

If needed I could open up the oil feed hole on the bottom of the shaft and better align the holes for the rocker arms. I just want to see if this is necessary before pulling everything apart.
 
I would check the shafts are installed correctly. It's "in the book" service manual that is, you can download 'em free at MyMopar.com
 
If you have everything installed correctly, I would take everything off and give them a good oil soaking (rockers/shafts) since everything is new. Then reinstall and check them again.
 
Yes for sure check the rocker installation. The rockers have a notch on one end of the shafts. the Notches should be down and to the left as you look at each side of the engine. This aligns the 1 enlarged rocker bolt hole on the underside of the shaft over the rocker pedestal through which the oil flows into the shafts. (2nd pedestal from the left on each side.)

Oil on the springs may helps spring cooling but IMHO is not all that necessary unless you are running extended high RPM's like in circle track racing. And the mechanism for 'throwing oil' is not really there; there is no 'cup' like for stamped rockers. Questoin: Are you getting oil on the tips of the valves, under the rockers?

The biggest thing for the 273 rockers is the pushrod cups; the oil HAS to be getting through the small hole in the adjuster side of the rockers so that it can then flow down around the adjuster and into the pushrod cups. Some of the shafts have a set of small holes on that side to insure better flow to the adjuster area. I would pull the covers and look to see that there is a lot of oil around the pushrod cups.

BTW, on your Mobil 1 (which I run in a lot of engines), are you running any any additives for ZDDP? The current crop of 10W30 oils for the street, marked for 'SN' service, don't have the levels of ZDDP that is considered adequate for cams with higher spring pressures.

Check out this chart; it shows all of the 10W30 Mobil 1 grades to have 900 PPM of zinc; your oil should be at 1200 or more for flat tappets with aftermarket springs.
https://mobiloil.com/~/media/amer/us/pvl/files/pdfs/mobil-1-oil-product-specs-guide.pdf
 
So why not run diesel oil ?
Not to hijack the post sorry ?

I have the same rockers on my 340 and they seem to run fine, could you have switch the sides on the shafts ?
 
The shafts can go on either side. Keep the notch down and to the left and each one works the same.

Be aware that the diesel oils are gradually undergoing the similar reductions in ZDDP. I have not kept up with that recently, but it is not as high in ZDDP as it has been in past specs. CJ-4 diesel oil specs limit phosphorous to 1200ppm, which means ZDDP is probably at 1300 ppm, which seems to be an adequate level for flat tappet use. But not all such CJ-4 oils actually have that level of phosphorous; I read one report of a CJ-4 at 1000 PPM of phosphorous which means ZDDP is at 1100 PPM, and that may be marginal, depending on the spring pressures.

And this is a useful read on ZDDP levels and current oils:
ZDDP Q&A - National Oil & Lube News
 
I'm 95% sure I have the shafts installed correctly, but I'll double check and look at the ball and cup as well to ensure there's oil in there.
My main concern is that the holes to the rockers aren't aligned and it's restricting oil flow.

Trapster- Mine runs great as well, but have you looked at the rockers while running? If so, is there a lot of oil flowing out the top onto the springs or very minimal?

I do use break in additive with the synthetic oil to increase zinc and protect flat tappet cam.
 
Realize that there is very little pressure up inside the rocker shafts, just a few psi. With banana grooves, there is very little to be misaligned.

As noted, some of the 273 shafts came with extra holes over towards the adjuster side, but those are just for helping the adjuster oiling.

FWIW.... /6 rockers flow very little while running; the oil just slowly dribbles over the valves.

Good deal on the additive! Just wanted to make sure.
 
Definitely revisit the installation of the rocker shafts! If you find that you had installed them incorrectly, you need to remove them, disassemble them and inspect them closely. Look for galling on the shafts and in the bottom of each rocker bore. If there is ANY galling, then you may have major problems. The shafts are case hardened, if they gall it sends shards of hardened material throughout engine. These will take out your oil pump, bearings, crank journals, etc.
if there is no galling, then you are almost golden. I agree with poster who advised to clean oil passages thoroughly in rockers. Make sure shafts are clean inside, also. Of course, also make sure the plugs are in both ends of the shafts.
ZDDP is not the be all end all additive in oil. And more ZDDP is not always better.There are other ingredients, such as moly, which are important, also. Google "rat blog oil", and read it, very informative.
 
The rocker shafts tend to fill with sludge, especially if they came from a high mileage engine that didn't recieve regular oil changes.

There are small "frost" style plugs in the shaft ends that you can pull to clean out the shafts.
 
SBM4theW!n said:
Finished putting 273 rockers on my LA 360 this spring and pulled off the oil cap a few days ago and while running there was very little oil coming out of the top hole of the rocker. Even when I revved it up I could see it pulsing but just a very slight trickle at best. I shut it off and looked at the springs and they looked almost dry. Everything seems fine, but I remember the old stamped rockers throwing oil everywhere.

Is this normal or a problem? I've heard the springs need oil to stay cool and don't want to hurt my new pushrods or valves.

Running 5-30 synthetic oil (hot), good oil pressure
Previous stamped rockers threw tons of oil
273 rockers with stock banana shafts, cleaned up with new adjusters
Shafts oriented correctly
At most 2 thin shims per rocker used to center rocker on valve
Car gets a lot of spirited driving through mountain roads hitting 6k often
Comp's Magnum 280H cam with matching Comp springs

If needed I could open up the oil feed hole on the bottom of the shaft and better align the holes for the rocker arms. I just want to see if this is necessary before pulling everything apart.
Click to expand...
the notch at end of shaft, goes to the front on drivers side and to rear on passenger side. this is from service book. also, notch goes down.
 
rustycowll69 said:
ZDDP is not the be all end all additive in oil. And more ZDDP is not always better.There are other ingredients, such as moly, which are important, also. Google "rat blog oil", and read it, very informative.
Click to expand...
MMMMM.... the issues with flat tappet cams showed up in the 2005-2006 timeframe, < a year after the mandate to lower the phosphorous levels in the lighter motor oils. So the conclusion about the importance of ZDDP is pretty clear. The question come up more about how much do you need and at what spring pressures (which drive lifter to lobe pressures). And yes, excess ZDDP can cause documented issues, but being at the 800 ppm level for a flat tappet cam and heavy springs is inviting lobe destruction. The prior limits were around 1200 ppm and flat tappet cams lived well on that.

Moly does not do what ZDDP does; read here on the latest research about how ZDDP appears to work:
Penn and ExxonMobil Researchers Address Long-standing Mysteries Behind Anti-wear Motor Oil Additive

I've read a lot of 540rat's stuff... some of it is very interesting. But I have also found at least one glaring error in his writings.
 
furyus2 said:
Are the bolt holes in the shims the same diameter as the oiling hole on the head?
Click to expand...
This is GOOD observation.... if the OP has shims UNDER the shafts. The hole in the underside of each shaft at the 2nd hole from the left is larger, to allow full flow from the rocker stand. A small shim hole at that location would restrict flow. This area is the controlling flow restriction in the stock oiling path to the rockers (after the 'cam interruptor').
 
nm9stheham said:
This is GOOD observation.... if the OP has shims UNDER the shafts. The hole in the underside of each shaft at the 2nd hole from the left is larger, to allow full flow from the rocker stand. A small shim hole at that location would restrict flow. This area is the controlling flow restriction in the stock oiling path to the rockers (after the 'cam interruptor').
Click to expand...

"At most 2 thin shims per rocker used to center rocker on valve."

I take it that he used the shims to move the rockers over the valve tips, I had to do the same I just installed the exact same setup on my motor do to the Harland Sharp rockers I had the geometry was so far off the only way to fix was to pull the heads and mill down the rocker pedestals, so I sold them. Hughes makes the correct geometry rockers, or so I am told they are also $800.00. Oh and the Harland Sharps I had were according to Harland Sharp were the 1st gen version rockers, I got used on Ebay...
 
I'm experiencing the exact same thing. I've put a couple hundred miles on them and everything seems fine. Just very little oil.
 
19blockhead72 said:
I'm experiencing the exact same thing. I've put a couple hundred miles on them and everything seems fine. Just very little oil.
Click to expand...
I have the 273 rockers on my 340, been on there for over 40 yrs. While there is maybe not as much oil flinging around as stamped rockers, there is plenty of oil coming out, and there has never been a problem.
 
There seems to be plenty of oil between the rockers and shafts just not much slinging down on the valves. Just the nature of the beast I guess.
 
19blockhead72 said:
There seems to be plenty of oil between the rockers and shafts just not much slinging down on the valves. Just the nature of the beast I guess.
Click to expand...
if it looks like not enough oil is coming out of the tips of the rockers, then I say trust your instincts and start looking at why. One poster suggested thoroughly cleaning out the oil passages, and I heartily agree with that as the first step. That and making sure the shafts are oriented correctly.
 
the 273 rocker is not going to pump same amount of oil the stamped rockers did. make sure shafts are in correctly. oil holes down and notch to front driver side notch to rear passenger side. now, we installed a restrictor plug @ .100 in each passage, in the block deck. have no wear issues, no galling, no bluing of pushrod ends. they been in there last 30 years.
 
perfacar said:
the 273 rocker is not going to pump same amount of oil the stamped rockers did. make sure shafts are in correctly. oil holes down and notch to front driver side notch to rear passenger side. now, we installed a restrictor plug @ .100 in each passage, in the block deck. have no wear issues, no galling, no bluing of pushrod ends. they been in there last 30 years.
Click to expand...
correct me if I'm wrong, (I haven't looked at a SB oiling diagram for over 30 years)don't the rocker shafts oil off of the cam bearings? If so, if the cam bearings were installed so the holes don't match up perfectly, couldn't that adversely affect the oil supply to the shafts? If I'm off base here, forgive me.
 
They don't have to match up perfectly (thoughI am not encouragin sloppy installation work). Even if they were offset by as much as 30% of the diameter, the resulting flow area is still larger than the smallest oil flow restriction before reaching the rocker shafts.

That smallest restriction is where the rocker hold-down bolt goes through the hole in the rockershaft, right above where the oil comes out of the rocker stand. The flow area of that smallest restriction is less than half of the flow area in the cam bearing holes.
 
The shims I'm referring to are around the shaft to align the rockers right to left. I didn't use the shims between the pedestals and the shaft because I didn't want them to affect the oiling hole on the pedestal, so I went with custom length pushrods instead. Also these shafts have the banana grooves and the additional hole for each rocker, so 8 oiling passages. Not sure if that changes anything.

I did check the cam bearings when I rebuilt the engine and the holes all lined up, and I cleaned up the all the valve-train and blasted them out with an air compressor. So there shouldn't be any restrictions.

It's possible these just don't pump a lot of oil to the valve and spring side. But per previous recommendations I'm going to check the ball and cup side and the the shaft for galling to be safe.
 
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